


hypothesis

by stardustupinlights



Series: so it goes [2]
Category: Yu-Gi-Oh! VRAINS
Genre: Alternate Universe - Canon Divergence, Anal Fingering, Asphyxiation, Bordering on Roleplay, Choking, Dirty Talk, Fluff and Smut, Idiots in Love, M/M, The sexy kind, Yuusaku is Kinky, ai is free, they're dating
Language: English
Status: Completed
Published: 2019-06-10
Updated: 2019-06-10
Packaged: 2020-04-24 03:40:32
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,298
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19165078
Author URL: https://archiveofourown.org/users/stardustupinlights/pseuds/stardustupinlights
Summary: Sometimes, having kinks is embarrassing. Yusaku is lucky his boyfriend is very accepting of them.





	hypothesis

**Author's Note:**

> self-indulgency is my kink. dom ryoken? check. yusaku being kinky? check. this is all.
> 
> not related to the other work on this series. i made this series it mainly because i like organization and also having one-offs nsfw fics is fun. please enjoy and give Celepom lots of love because she beta'ed this a while back becuse i forgot i wrote this in December. 
> 
> don't be afraid of the kudos button. it don't bite.

Ryoken has a slight suspicion that Yusaku is hiding something from him after the third time he realizes he's actively holding his breath while giving him a blowjob. No matter where, when, under what circumstances, he’s doing it frequently and seemingly without realizing it. But every time Ryoken questions it, Yusaku brushes it off with this weird look in his eye, making him antsy and worried. So, in an effort to figure out what’s happening, he starts gathering clues and eventually comes up with three facts that justify his suspicions that this isn’t just some bizarre occurrence:

  1. Yusaku rarely keeps anything from him since they became friends, and much less so now that they're actually dating.
  2. Yusaku isn't usually shy about what he wants before, during, or after sex, so his lack of an explanation is odd.
  3. He's noticed that Yusaku tends to do this thing of holding his breath a lot, and he believes half of the time it isn’t as unconscious as he likes to pretend.



By this point, about a month and a half into his hypothesis that there’s something being kept from him, the situation called for conflict. Because if there was anything about their nightly (frequently daily) activities that was making Yusaku hold his breath so often and so randomly, he needed to know. His most prominent theory, since Yusaku did it mostly during blowjobs, was that he was accidently choking him and he was too stubborn to admit it. The second theory was that he smelled, but his personal hygiene is so intense than even Yusaku himself thinks it’s ridiculous, so he was leaning more towards the first. Otherwise, he has absolutely no idea what this is about.

He brings it up over coffee after walking down from the mansion to see Café Nagi up and running. Kusanagi-san is putting out the tables and chairs with Yusaku’s help. He contributes, mainly because he wants to sit down and get this conversation over with, but he has to wait until Kusanagi leaves before daring to speak; wary of accidentally given away private information about their sex-capades. Kusanagi-san could never find out about how Yusaku only ever takes breaks to give him blowjobs and get a rim job almost on a daily basis. He’s so glad that annoying AI is not stuck on Yusaku’s wrist twenty-four-seven anymore.

"So, about that holding your breath thing you do—" He begins, his voice as innocent as it never is, but he doesn’t get any further before Yusaku is slamming his boiling hot cup of black coffee on the table a bit more urgently than he needed to.

"I already told you it's nothing," Yusaku interrupts, talking quickly, words coming out of his mouth a pitch higher than his usual monotonous tone, which is odd. A bit of coffee lands on his hand, but he’s quick to lick it off, not making any eye contact. "You can drop the subject."

Ryoken stares at Yusaku's hands wrapping aggressively around his cup, thinks it over, and then shakes his head, taking a sip from his own coffee. "Sorry, I can't accept that. You need to tell me what's bothering you."

"Your questioning is," Yusaku mumbles, puffing out his cheeks, and Ryoken almost coos at how cute he looks in the morning, face still puffy with sleep and hair a bit more tussled than usual. He's skipping his first hour of class, not that Ryoken approves, but he's the one helping him with some classes anyways and he gets to actually spend some time with him, so all is good. "Also, aren't you usually the one who doesn't want to talk about our sex life in public?"

"Kusanagi-san won't be back until later, and you left that nuisance of an Ignis in the truck. Also, Homura's actually in class." Feeling bold, Ryoken scoots over his chair to sit closer to him and wraps an arm around his shoulders, smirking a smug smile when Yusaku immediately leans into him. "I'd say we're pretty alone."

"I still don't want to talk about it," Yusaku pouts, and humming in mild agreement, Ryoken grabs his chin and tilts his face up to kiss him deeply and slowly, wanting to make sure of one thing. Yusaku reciprocates openly, parting his lips as Ryoken's tongue peeks out, and as he feels Yusaku pull him closer by the neck of his shirt, he takes stock of the fact that he cannot hear nor feel Yusaku's breathing at all. He gives it a couple more of seconds and ups the intensity of the kiss to see if there's any change, and draws back when he notices none, ignoring Yusaku's groan of displeasure.

Yusaku tries to sneakily take in a deep breath, but Ryoken is onto him now.

"You were not breathing at all during that kiss," Ryoken raises his eyebrows, and Yusaku stares at him in growing annoyance. "Talk to me?"

"You won't like it," Yusaku admits, shoulders dropping hesitantly, but his face remains impassive; it's clear he's thought about this before, and it troubles Ryoken. Just how long has this been going on without him noticing? "It's not your thing."

"You're my thing, actually, so—"

"That's part of the problem, Ryoken," Yusaku frowns, giving him this look like he knows what he’s talking about and he should shut the fuck up. Ryoken does not appreciate it and frowns back, confused about how Yusaku being his thing could be a problem in this case, when it usually never is. “You wouldn’t know what to do if I told you.”

“ _But_ we could work through that if you talked to me,” Ryoken points out, and Yusaku actually crosses his arms to throw him a glare, so Ryoken sighs in exasperation, not understanding why Yusaku can’t talk about this when he’s usually the one to bring up most of their sex related talks. “At least tell me why you being my thing is part of the problem.”

Yusaku stares for a few seconds and then rolls his eyes, turning back to his coffee thoughtfully. Ryoken waits, because with Yusaku silence isn’t necessarily a no – it took him longer than it should have to realize this applied to almost any subject – and turns to watch the sight of waves crashing against the beach, birds flying happily and diving down into the water to catch an unlucky fish from time to time, the breeze running through his hair and smelling of sea water. The weather’s been extremely nice lately, and he’s been wanting to take Yusaku out for a boat ride, so he’ll make sure to ask today about spending the weekend together, just the two of them off Den City’s coast, no one around to bother them and with the advantage of being as loud as they want…

“You won’t like it because it involves… actively hurting me,” Yusaku whispers from behind him, and Ryoken turns to look at his face, surprised. He… definitely wasn’t expecting this. Yusaku straightens up on his seat, looking at him head on, almost likes he’s going to declare war against the Knights of Hanoi. “I suspect I may have an asphyxiation kink.”

Ryoken takes a few seconds to process this, and blinks at him as pieces of the puzzle fall together in his mind: holding his breath, not telling him about it, doing it mostly during blowjobs, both on purpose and without meaning to— oh, he thinks, that makes sense.

“Well, you could have just said so,” Ryoken says, very awkwardly, and Yusaku blushes prettily from below his neckline to his ears, shooting him a glare. “Is that all?”

“‘ _Is that all,’_ really?” Yusaku rolls his eyes again, and Ryoken leans in to drop an apologetic kiss on his cheek, right under that pale mole under his eye. Yusaku scrunches up his nose like he’s disgusted by that, but the quirk of his lips says otherwise, so Ryoken drops another one over them, making him smile. “You’re still an idiot.”

“But I’m your idiot,” Ryoken mumbles against his skin, and Yusaku leans back to bring his hand up and get his own fringe out of the way, scrunching up his nose at the cheesiness of the comment. Ryoken slightly laments this distance, but it does not upset him. “I wish you’d told me about this kink of yours sooner. I was scared you not breathing while giving me blowjobs meant I accidentally choked you every time.”

“Speaking of, I’m never giving you a blowjob again if you ever bring this back up,” Yusaku threatens, rolling his eyes, and Ryoken can’t help but snort. _As if._ Yusaku’s intense, accusatory glare just looks cute to him, which may prove that there’s something wrong with him, because that glare usually would make grown men cower and babies cry. “What’s so funny?”

“Ah, so we’re going to pretend you don’t beg for it at least three times a week?” He asks, a bit cheekily if he’s being honest, and Yusaku turns cherry red, turning away from him and hiding behind his coffee cup, making Ryoken chuckle and lean in to kiss his temple, but Yusaku’s hand shooting up to hold his face stops him. Ryoken kisses that instead, which just makes Yusaku shake his head a bit helplessly.

“Shut up,” he mumbles, weakly, and Ryoken decides to change the subject to his schoolwork, lest he accidentally make his boyfriend spontaneously combust.

Ryoken leaves shortly after that, once Kusanagi-san is back from last minute sausage shopping – _‘Takeru forgot to make the order again, I_ swear _this kid is a disaster,’_ — and Yusaku reassures him that _‘yes mom I will be going to school today don’t worry’_. He smacks Yusaku’s ass as a punishment for his petulance in front of both Kusanagi-san and the Dark Ignis, getting a good handful of that sweet butt, and they both laugh it off like it’s the funniest thing they’ve seen in their life, most likely to deal with the trauma. But the last look Ryoken exchanges with Yusaku as he takes the stairs back to his house tells him all he needs to know about how he feels about their earlier conversation: ashamed, embarrassed, probably regretful that he even said anything, and Ryoken was going to fix that. He couldn’t have Yusaku feeling like that about a _kink_ , of all things.

He thinks about it throughout the day, wondering whether this was a thing he would be into or not— Yusaku had a point saying that Ryoken wasn’t that much of a fan of hurting him, at least not in a way that would be permanently damaging or unbeneficial for both of their pleasure. And after doing some research and still not settling on an answer, Ryoken takes a break from his current task of finishing a commission program for SOL that he still can’t believe they don’t have the right staff or budget to do themselves, and imagines how it would go.

Yusaku has a tendency to get vocal when Ryoken indulged him with his favorite kinks, so that was a must, considering how often he seemed to hold his own breath lately… he also locked him in an almost bruising grip, and shivered when his hand grazed over his weak points like, case in point, his neck. Ryoken pictures having Yusaku sprawled out underneath him, legs wrapped around his waist while he’s in the midst of pushing in and out of him, hearing his breath quickening with each of the movements of his hips, pictures reaching out to caress him from his bellybutton to his nipples to stop at the base of his neck, wrapping his fingers around it loosely, Yusaku begging for Ryoken to choke him as he teased him with little amounts of pressure here and there until he finally gave in and squeezed firmly, maintaining just enough strength to cut his air supply, making him moan breathlessly and come all over his chest—

Ryoken very ironically takes a deep, calming breath. Then, he nods to himself, closes his eyes, and wills his sudden erection away, because he’s getting none of that today, seeing as Yusaku won’t be physically available to him until the weekend unless he wanted to contribute to him skipping class and not studying to steal hotdogs and coffee from Café Nagi. Which, _tempting_ , but he doesn’t want to be a worse role model than he already is.

Instead, Ryoken bides his time and doesn’t mention the kink again. He invites Yusaku on the boat getaway, convinces him to leave any technology that isn’t related to homework with Kusanagi-san – Homura was not to be trusted with any tech device, not even his own phone. He learned that the hard way – and waits until Yusaku’s given him an exhausting but world-shattering blowjob to lift him on top of the meeting room table and get two fingers deep inside him, holding his hands over his head with one of his own and standing almost fully clothed over him, his legs on top on each of Ryoken’s shoulders by the ankles to keep a good finger-fucking angle and his hips twitching and rotating to the rhythm Ryoken’s set with his hand, slow and torturous.

“Remember what we talked about the other day?” Ryoken asks, just a tiny bit breathless as he watches his boyfriend, who’s as naked as the day he was born, pant with the effort of holding himself up with his own legs while still trying to get some friction. He’s certainly not making it easy for him, holding his hands down like that and not stepping closer.

“Hm?” Yusaku hums, frowning in confusion, and momentarily squeezes his eyes shut when Ryoken gives him a particularly harsh thrust, a helpless little moan slipping out of him. “What— what’d you just say?”

Ryoken gears himself up by taking a step closer and leaning down over him, making him bring his knees up to his shoulders, his breath freezing as Ryoken lets go of his hands to trace his lips with his fingertips, dragging them down to his neck until he’s on the ideal position to loosely wrap his hand around it without applying any pressure. Yusaku seems to go back to breathing in a rush, his intake of air so loud Ryoken almost flinches back from it, and he sees goosebumps break out on his skin, his eyes widening in disbelief.

“Just say the word,” Ryoken whispers, dropping a kiss on his parted lips that are still looking quite red and swollen from the blowjob he got earlier. Yusaku audibly swallows, and he can’t help but smirk down at him, thinking that this was definitely a good idea. “Say the word and I’ll make it happen, love.”

Yusaku lets out a desperate sound, apparently in the process of rebooting his brain to assess the situation, and after three exact seconds – Ryoken wonders if they were both counting – he whimpers, nodding enthusiastically, rotating his hips twice to get Ryoken to move again, making him realize he stopped fingering him at some point to focus on this. He wiggles his fingers around playfully, and one of Yusaku’s legs twitches violently on his shoulder, making him chuckle.

“Please, Ryoken,” he finally gasps out, bringing his hands up to grab at his hair tightly, his ass squeezing the life out of his fingers. They’ll need more lube pronto if they wait for too long to do this. “Please, c’mon, Ryoken, _please choke me—”_

“Shit, okay,” Ryoken whispers to himself, not expecting the flare of heat that strikes him as a lightning bolt would, and barely keeps himself from squeezing his hand without giving Yusaku a warning. “Get your breath under control, better safe than sorry.”

Yusaku nods again, and Ryoken stops himself from making any movements, waits until he watches him relax, his breathing going from borderline hyperventilating to something more calm, and he counts to three in his head, the rise and fall of his chest getting under control, before he properly wraps his hand around the base of his neck and squeezes. Logically, the rise and fall of Yusaku’s chest stops now that his wind pipe is blocked, hooded eyes looking up at him with intensity and still some disbelief inside them, his pupils blown with arousal. It makes Ryoken feel powerful in a way, knowing that Yusaku trusts him with his life, that he doesn’t hesitate to give Ryoken permission to do this and is even begging him for it. It makes a little groan slip out of him, so he starts to move his fingers inside of Yusaku again, as slow as he was before, while keeping his grip on his neck steady.

It feels like a lot of time has passed, but in reality there’s barely a second of difference between the moment in which he cuts Yusaku’s air supply and the movement of fingers; it earns him a broken, choked off moan that vibrates under his hand, making him shiver, and mindful of the fact that Yusaku won’t be able to go forever without breathing, Ryoken curls his fingers sharply and growls hungrily at the answering twitch of his hips, wishing he was inside that lovely, tight, familiar heat, another muted whimper getting drawn from Yusaku’s parted lips and not finding anywhere to go.

Ryoken wishes they were doing this like in his fantasy, but he’s glad that they aren’t for their first time, because this feeling of power, the tightness of Yusaku’s ass, the vibration of sounds he can’t make under his hand, the beauty of his naked skin, the amount of trust he’s been given… all of that combined would have probably made him lose it and get sloppy, which can’t happen because this is sort of dangerous, so he’s really thankful for Yusaku’s eagerness to blowjob his libido out for a little while; there was nothing better than coming down his throat while looking down at him swallowing like he’s desperate for it. Except actually getting to fuck him.

Seeing as his hands are both busy, Yusaku takes it over himself to drive his body closer to orgasm and drops one of his hands to his stomach from where they were clutching at his hair to grab at his own cock, pumping it to Ryoken’s same punishing rhythm. The moan that slips out of Ryoken’s mouth at that is involuntary and reciprocated by another tight squeeze of Yusaku’s ass around his fingers, so, for the sake of milking this situation for all its worth, Ryoken picks up the pace, actually bothering to look for Yusaku’s prostate for the first time that evening, and rubbing against it hard when he finds it.

The sound Yusaku tries to make was probably a high pitched, short-lived scream, but with how things are, he only succeeds in dropping his mouth open, slamming his head back against the table worryingly hard and making Ryoken lose some of his grip when he finds himself unprepared for the violent squirming of his body. He’s quick to steel his grip back into place before Yusaku falls into distress, and locks eyes with him once he manages to get them open, crystal clear blue meeting vibrant green for the millionth time since they’ve met, and Ryoken groans at Yusaku’s blissed out expression; features completely slack and relaxed as he allows his world to be reduced to his hand on his cock, Ryoken’s fingers in his ass slamming against his prostate, and the hand against his neck cutting him off from breathing in. He can only imagine the weightlessness he feels and Ryoken is aching in his pants by now, just from watching him lose it, his mind becoming a bit foggy as the need to make Yusaku come from this fills him, so his next words slip out of his mouth freely, without shame or hesitation.

“Is this what you wanted?” He starts, Yusaku whole face twitching with the question. Ryoken continues, glad to have his attention. “To hold you down at my mercy, no way of escaping even if you wanted to?”

Yusaku seems to try to swallow, but fails and instead stares, biting his lip in a way that looks pretty painful and serves to bring out the redness of them. His hips start to move faster, letting Ryoken know the dirty talk is getting to him, so he leans in to capture his mouth and press a hard, wet kiss against his lips, enjoying the way in which Yusaku scrambles to reciprocate by lifting his head as much as he can, which is not much. He bites at his bottom lip, pulls back and lets it go before sucking it back into his mouth, saliva dripping down Yusaku’s chin and connecting their lips until Ryoken leans away slightly, his boyfriend shivering hopelessly and squeezing his ass around fingers yet again.

“I can’t believe how needy you are,” Ryoken clicks his tongue, shaking his head in fake disapproval. “What would the innocent people of Link VRAINS think of their savior if they saw him now, hm? Begging to be choked and getting off on it?”

Yusaku closes his eyes tightly, legs suddenly pushing Ryoken’s body away only for then wrap around his waist, bringing his crotch closer to where his fingers are fucking into him. Yusaku seemed to have forgotten about his hand on his cock, somehow, seeing as it’s not moving, and Ryoken watches his tip leaking out some pre-cum onto his stomach with interest, licking his lips, wondering what he can do to help.

“What’s this, now? You want my cock, is that it?” Ryoken smirks, and Yusaku squeezes him with every part of his body that is around him in what he assumes is agreement, with the hand buried in his hair and pulling harshly, his legs around his waist, his ass greedily sucking his fingers in and trying to keep him buried. Ryoken feigns pity over his predicament, eyes wandering over Yusaku’s body like he’s judging an art piece when in reality he’s just about dying to get off, high on everything that Yusaku is offering him. He loosens his hand up a little and gives him time to breathe, worried about how much time he’s been going without air, and at his immediate frown of protest, he only shakes his head and gives it a moment before tightening it again. They could test their limits another day, but for now…

Channeling that dark, husky undertone that comes out naturally whenever he’s using his Link VRAINS avatar, Ryoken leans down to whisper on Yusaku’s ear, letting his smile graze his skin teasingly. “Are you gonna come, _Yusaku_? Or do you need a cock up your ass to do that?”

At that, Yusaku mewls, his whole boy squirming. Seemingly remembering he has a dick, Yusaku frantically touches himself like he’s about to come, rubbing himself fast and hard as his breathing goes nuts, with his thumb sliding over his slit clumsily and his hands shaking through every movement. Ryoken huffs out a breath, way too turned on and hypnotized by this display, so he moves over to kiss him, simultaneously twisting his fingers inside Yusaku and increasing the pressure on his neck beyond what he’s been going with, eager to see him come— no, needing to see him give in to the pleasure; no matter how many times Ryoken gets to see him like this he always enjoys it like it’s the first, and this isn’t an exception, only made better by the feeling of power his hand over his throat gives him.

Yusaku seems to lose it even further, his hips stuttering in confusion over whether to go down on Ryoken’s fingers or up his fist, and with a definitive breathless, soundless cry if it weren’t for a couple of strangled sounds, he comes all over Ryoken’s shirt and his own chest, body writhing and oversensitive with the effort of Ryoken’s fingers pushing against his prostate through it without stopping, back arching beautifully until it stops and he becomes jelly in his arms, limbs settling against the table and his legs shaking, struggling to stay around his waist.

Ryoken immediately lifts his hand away from Yusaku’s neck, watches him breathe in slowly with faraway eyes that are just a bit moist, and only once he’s sure he’s coming down from his high does he dare to talk:

“I take it you liked that,” he comments, trying to be casual, but some disbelief slip into his voice still. He’s also beyond turned on, his cock aching almost painfully in his pants, so it’s a distraction he doesn’t need. Swallowing, Ryoken shoots Yusaku a smile. “I thought that this wasn’t my thing?”

Yusaku finds it in himself to throw him a glare as he sits up, wincing at his probably stiff limbs and grabbing onto Ryoken’s shoulder to keep himself upright. He’s a real mess right now, but Ryoken thinks it’s cute, so he helps him by wrapping his arms around him to hold him up, his hands caressing the skin of that back of his thighs and his cock throbbing when he notices a shiver running through him.

“Next time, you could just say _‘Yusaku that’s a great kink, we should totally try it out.’_ Instead of, you know, surprising me with the proposition out of the blue,” he says, his voice rough and scratchy. Ryoken smiles, dropping his head on his shoulder so he won’t see it. Yusaku huffs. “I know you’re laughing!”

“You’re cute,” he shrugs, chuckling at Yusaku’s disgusted sound. There’s marks of his fingers on the side of his neck, and the sight sends a trill down his spine. “Any other kinks I need to know about?”

Silence.

“… have you ever thought about strip dueling?”

**Author's Note:**

> no, i do not have a strip duel written.
> 
> yet.
> 
> also don't trust the method used for the choking/asphyxiation in this fic. be safe. use signals and safewords. yes, this is a disclaimer and a call out to myself. i hope you guys enjoyed that regardless!


End file.
